In order to preserve wood, preservative material is introduced into the wood. One way to introduce preservation material into the wood is in accordance with an autoclave process, wherein the material to be treated, such as wood, is placed within a vessel. Preservative or penetrating fluid is introduced into the vessel and it is closed. The vessel is heated thereby reducing the viscosity of the penetrating fluid and enhancing capillary action due to a slight increase in pore size in the pores of the wood, and a slight increase in pressure of the fluid due to thermal expansion.
Another way to introduce preservative material into the wood is by the osmosis process whereby water soluble salts are used whereby ion migration occurs across the cellular walls of the wood as a result of the moisture within the wood cells.
A further way to introduce preservative material into the wood is by way of the liquified petroleum gas process which involves the use of the liquified petroleum as a solvent to carry the preservative material within the wood, and this is done under a pressure of 75-100 p.s.i.
None of the foregoing processes are effective to distribute the preservative material throughout no more than 15 to 20 percent of the wood to be preserved. Thus, the outer area of the wood is preserved, and, after a period of time depending upon the environment, dterioration and decay of the wood begins.
The present invention causes the penetrating or preservative fluid to be distributed throughout 95 percent of the material to be treated by raising the pressure on the penetrating fluid by incremental levels, and intermediate each level the pressure is permitted to reach equilibrium with the functional and other forces being generated within the wood as the fluid thereinto. These incremental pressure equilibriums are continued until a maximum pressure is attained whereby expected penetration throughout substantially all of the wood by the fluid has occurred.
A primary object of the present invention is to provide a novel method for controllably introducing penetrating fluid into material.
Another object of the invention is the provision of a simple and efficient apparatus to carry out this method of treating material.
A further object of the invention is to provide treated material that has penetrating fluid throughout most thereof.
Still another object of the invention is the provision of treated material of uniform quality.